fix version string; new release

Author: dgoffredo

src/datadog/tracer.cpp

@@ -208,7 +208,7 @@ Expected<ExtractedData> extract_data(ExtractionPolicy& extract,
   return extracted_data;
 }
 
-void log_startup_message(Logger& logger, std::string_view tracer_version,
+void log_startup_message(Logger& logger, std::string_view tracer_version_string,
                          const Collector& collector,
                          const SpanDefaults& defaults,
                          const TraceSampler& trace_sampler,
@@ -219,7 +219,7 @@ void log_startup_message(Logger& logger, std::string_view tracer_version,
                          std::size_t tags_header_max_size) {
   // clang-format off
   auto config = nlohmann::json::object({
-    {"version", tracer_version},
+    {"version", tracer_version_string},
     {"defaults", to_json(defaults)},
     {"collector", collector.config_json()},
     {"trace_sampler", trace_sampler.config_json()},
@@ -270,9 +270,10 @@ Tracer::Tracer(const FinalizedTracerConfig& config,
   }
 
   if (config.log_on_startup) {
-    log_startup_message(*logger_, tracer_version, *collector_, *defaults_,
-                        *trace_sampler_, *span_sampler_, injection_styles_,
-                        extraction_styles_, hostname_, tags_header_max_size_);
+    log_startup_message(*logger_, tracer_version_string, *collector_,
+                        *defaults_, *trace_sampler_, *span_sampler_,
+                        injection_styles_, extraction_styles_, hostname_,
+                        tags_header_max_size_);
   }
 }
 

src/datadog/version.cpp

@@ -3,7 +3,8 @@
 namespace datadog {
 namespace tracing {
 
-const std::string_view tracer_version = "0.0.0";
+const char* const tracer_version = "v0.1.1";
+const char* const tracer_version_string = "[dd-trace-cpp version v0.1.1]";
 
 }  // namespace tracing
 }  // namespace datadog

src/datadog/version.h

@@ -1,15 +1,19 @@
 #pragma once
 
 // This component provides the release version of this library.
-// `tracer_version` is sent to the Datadog Agent with each trace, and is printed
-// to the log whenever `Tracer` is initialized.
 
 #include <string_view>
 
 namespace datadog {
 namespace tracing {
 
-extern const std::string_view tracer_version;
+// The release version at or before this code revision, e.g. "v0.1.1".
+extern const char *const tracer_version;
+
+// A string literal that contains `tracer_version` but also is easier to `grep`
+// from the output of the `strings` command line utility, e.g. "[dd-trace-cpp
+// version v0.1.1]".
+extern const char *const tracer_version_string;
 
 }  // namespace tracing
 }  // namespace datadog